Upgrading Windows 10 Home To Pro With Old Windows 7 Pro Key

Right Click on This PC and select Properties and then select change product key. (or press Windows key + R and type in slui.exe 3 )

Type in the following generic Windows 10 PRO key (you can’t activate with it but it will allow the upgrade).

VK7JG-NPHTM-C97JM-9MPGT-3V66T

After this follow the prompts to update to Pro. Once updated and rebooted then attach the PC to the Internet. Go in and change the key the same way and now type in your Windows 7,8 or 10 Pro key. Then activate.